read from cookie every time init is called since cookie name might change
update iframe loader in README
Ignore clicks on flash objects

Chrome for Linux using PepperFlash tends to bubble click events between
flash and JavaScript.  This causes problems if the flash object requires
the ability to handle multiple fast clicks and boomerang spends some
time figuring out what the target of the click was.

This patch ignores clicks if they occurred on a flash object.
fix a whole bunch of jslint errors